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Diffstat (limited to 'libsolidity/Parser.cpp')
| -rw-r--r-- | libsolidity/Parser.cpp | 1082 |
1 files changed, 1082 insertions, 0 deletions
diff --git a/libsolidity/Parser.cpp b/libsolidity/Parser.cpp new file mode 100644 index 00000000..fbf8478d --- /dev/null +++ b/libsolidity/Parser.cpp @@ -0,0 +1,1082 @@ +/* + This file is part of cpp-ethereum. + + cpp-ethereum is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + cpp-ethereum is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with cpp-ethereum. If not, see <http://www.gnu.org/licenses/>. +*/ +/** + * @author Christian <c@ethdev.com> + * @date 2014 + * Solidity parser. + */ + +#include <vector> +#include <libdevcore/Log.h> +#include <libevmasm/SourceLocation.h> +#include <libsolidity/Parser.h> +#include <libsolidity/Scanner.h> +#include <libsolidity/Exceptions.h> +#include <libsolidity/InterfaceHandler.h> + +using namespace std; + +namespace dev +{ +namespace solidity +{ + +/// AST node factory that also tracks the begin and end position of an AST node +/// while it is being parsed +class Parser::ASTNodeFactory +{ +public: + ASTNodeFactory(Parser const& _parser): + m_parser(_parser), m_location(_parser.getPosition(), -1, _parser.getSourceName()) {} + ASTNodeFactory(Parser const& _parser, ASTPointer<ASTNode> const& _childNode): + m_parser(_parser), m_location(_childNode->getLocation()) {} + + void markEndPosition() { m_location.end = m_parser.getEndPosition(); } + void setLocation(SourceLocation const& _location) { m_location = _location; } + void setLocationEmpty() { m_location.end = m_location.start; } + /// Set the end position to the one of the given node. + void setEndPositionFromNode(ASTPointer<ASTNode> const& _node) { m_location.end = _node->getLocation().end; } + + template <class NodeType, typename... Args> + ASTPointer<NodeType> createNode(Args&& ... _args) + { + if (m_location.end < 0) + markEndPosition(); + return make_shared<NodeType>(m_location, forward<Args>(_args)...); + } + +private: + Parser const& m_parser; + SourceLocation m_location; +}; + +ASTPointer<SourceUnit> Parser::parse(shared_ptr<Scanner> const& _scanner) +{ + m_scanner = _scanner; + ASTNodeFactory nodeFactory(*this); + vector<ASTPointer<ASTNode>> nodes; + while (_scanner->getCurrentToken() != Token::EOS) + { + switch (m_scanner->getCurrentToken()) + { + case Token::Import: + nodes.push_back(parseImportDirective()); + break; + case Token::Contract: + nodes.push_back(parseContractDefinition()); + break; + default: + BOOST_THROW_EXCEPTION(createParserError(std::string("Expected import directive or contract definition."))); + } + } + return nodeFactory.createNode<SourceUnit>(nodes); +} + +std::shared_ptr<const string> const& Parser::getSourceName() const +{ + return m_scanner->getSourceName(); +} + +int Parser::getPosition() const +{ + return m_scanner->getCurrentLocation().start; +} + +int Parser::getEndPosition() const +{ + return m_scanner->getCurrentLocation().end; +} + +ASTPointer<ImportDirective> Parser::parseImportDirective() +{ + ASTNodeFactory nodeFactory(*this); + expectToken(Token::Import); + if (m_scanner->getCurrentToken() != Token::StringLiteral) + BOOST_THROW_EXCEPTION(createParserError("Expected string literal (URL).")); + ASTPointer<ASTString> url = getLiteralAndAdvance(); + nodeFactory.markEndPosition(); + expectToken(Token::Semicolon); + return nodeFactory.createNode<ImportDirective>(url); +} + +ASTPointer<ContractDefinition> Parser::parseContractDefinition() +{ + ASTNodeFactory nodeFactory(*this); + ASTPointer<ASTString> docString; + if (m_scanner->getCurrentCommentLiteral() != "") + docString = make_shared<ASTString>(m_scanner->getCurrentCommentLiteral()); + expectToken(Token::Contract); + ASTPointer<ASTString> name = expectIdentifierToken(); + vector<ASTPointer<InheritanceSpecifier>> baseContracts; + vector<ASTPointer<StructDefinition>> structs; + vector<ASTPointer<EnumDefinition>> enums; + vector<ASTPointer<VariableDeclaration>> stateVariables; + vector<ASTPointer<FunctionDefinition>> functions; + vector<ASTPointer<ModifierDefinition>> modifiers; + vector<ASTPointer<EventDefinition>> events; + if (m_scanner->getCurrentToken() == Token::Is) + do + { + m_scanner->next(); + baseContracts.push_back(parseInheritanceSpecifier()); + } + while (m_scanner->getCurrentToken() == Token::Comma); + expectToken(Token::LBrace); + while (true) + { + Token::Value currentToken = m_scanner->getCurrentToken(); + if (currentToken == Token::RBrace) + break; + else if (currentToken == Token::Function) + functions.push_back(parseFunctionDefinition(name.get())); + else if (currentToken == Token::Struct) + structs.push_back(parseStructDefinition()); + else if (currentToken == Token::Enum) + enums.push_back(parseEnumDefinition()); + else if (currentToken == Token::Identifier || currentToken == Token::Mapping || + Token::isElementaryTypeName(currentToken)) + { + VarDeclParserOptions options; + options.isStateVariable = true; + options.allowInitialValue = true; + stateVariables.push_back(parseVariableDeclaration(options)); + expectToken(Token::Semicolon); + } + else if (currentToken == Token::Modifier) + modifiers.push_back(parseModifierDefinition()); + else if (currentToken == Token::Event) + events.push_back(parseEventDefinition()); + else + BOOST_THROW_EXCEPTION(createParserError("Function, variable, struct or modifier declaration expected.")); + } + nodeFactory.markEndPosition(); + expectToken(Token::RBrace); + return nodeFactory.createNode<ContractDefinition>( + name, + docString, + baseContracts, + structs, + enums, + stateVariables, + functions, + modifiers, + events + ); +} + +ASTPointer<InheritanceSpecifier> Parser::parseInheritanceSpecifier() +{ + ASTNodeFactory nodeFactory(*this); + ASTPointer<Identifier> name(parseIdentifier()); + vector<ASTPointer<Expression>> arguments; + if (m_scanner->getCurrentToken() == Token::LParen) + { + m_scanner->next(); + arguments = parseFunctionCallListArguments(); + nodeFactory.markEndPosition(); + expectToken(Token::RParen); + } + else + nodeFactory.setEndPositionFromNode(name); + return nodeFactory.createNode<InheritanceSpecifier>(name, arguments); +} + +Declaration::Visibility Parser::parseVisibilitySpecifier(Token::Value _token) +{ + Declaration::Visibility visibility(Declaration::Visibility::Default); + if (_token == Token::Public) + visibility = Declaration::Visibility::Public; + else if (_token == Token::Internal) + visibility = Declaration::Visibility::Internal; + else if (_token == Token::Private) + visibility = Declaration::Visibility::Private; + else if (_token == Token::External) + visibility = Declaration::Visibility::External; + else + solAssert(false, "Invalid visibility specifier."); + m_scanner->next(); + return visibility; +} + +ASTPointer<FunctionDefinition> Parser::parseFunctionDefinition(ASTString const* _contractName) +{ + ASTNodeFactory nodeFactory(*this); + ASTPointer<ASTString> docstring; + if (m_scanner->getCurrentCommentLiteral() != "") + docstring = make_shared<ASTString>(m_scanner->getCurrentCommentLiteral()); + + expectToken(Token::Function); + ASTPointer<ASTString> name; + if (m_scanner->getCurrentToken() == Token::LParen) + name = make_shared<ASTString>(); // anonymous function + else + name = expectIdentifierToken(); + VarDeclParserOptions options; + options.allowLocationSpecifier = true; + ASTPointer<ParameterList> parameters(parseParameterList(options)); + bool isDeclaredConst = false; + Declaration::Visibility visibility(Declaration::Visibility::Default); + vector<ASTPointer<ModifierInvocation>> modifiers; + while (true) + { + Token::Value token = m_scanner->getCurrentToken(); + if (token == Token::Const) + { + isDeclaredConst = true; + m_scanner->next(); + } + else if (token == Token::Identifier) + modifiers.push_back(parseModifierInvocation()); + else if (Token::isVisibilitySpecifier(token)) + { + if (visibility != Declaration::Visibility::Default) + BOOST_THROW_EXCEPTION(createParserError("Multiple visibility specifiers.")); + visibility = parseVisibilitySpecifier(token); + } + else + break; + } + ASTPointer<ParameterList> returnParameters; + if (m_scanner->getCurrentToken() == Token::Returns) + { + bool const permitEmptyParameterList = false; + m_scanner->next(); + returnParameters = parseParameterList(options, permitEmptyParameterList); + } + else + returnParameters = createEmptyParameterList(); + ASTPointer<Block> block = ASTPointer<Block>(); + nodeFactory.markEndPosition(); + if (m_scanner->getCurrentToken() != Token::Semicolon) + { + block = parseBlock(); + nodeFactory.setEndPositionFromNode(block); + } + else + m_scanner->next(); // just consume the ';' + bool const c_isConstructor = (_contractName && *name == *_contractName); + return nodeFactory.createNode<FunctionDefinition>(name, visibility, c_isConstructor, docstring, + parameters, isDeclaredConst, modifiers, + returnParameters, block); +} + +ASTPointer<StructDefinition> Parser::parseStructDefinition() +{ + ASTNodeFactory nodeFactory(*this); + expectToken(Token::Struct); + ASTPointer<ASTString> name = expectIdentifierToken(); + vector<ASTPointer<VariableDeclaration>> members; + expectToken(Token::LBrace); + while (m_scanner->getCurrentToken() != Token::RBrace) + { + members.push_back(parseVariableDeclaration()); + expectToken(Token::Semicolon); + } + nodeFactory.markEndPosition(); + expectToken(Token::RBrace); + return nodeFactory.createNode<StructDefinition>(name, members); +} + +ASTPointer<EnumValue> Parser::parseEnumValue() +{ + ASTNodeFactory nodeFactory(*this); + nodeFactory.markEndPosition(); + return nodeFactory.createNode<EnumValue>(expectIdentifierToken()); +} + +ASTPointer<EnumDefinition> Parser::parseEnumDefinition() +{ + ASTNodeFactory nodeFactory(*this); + expectToken(Token::Enum); + ASTPointer<ASTString> name = expectIdentifierToken(); + vector<ASTPointer<EnumValue>> members; + expectToken(Token::LBrace); + + while (m_scanner->getCurrentToken() != Token::RBrace) + { + members.push_back(parseEnumValue()); + if (m_scanner->getCurrentToken() == Token::RBrace) + break; + expectToken(Token::Comma); + if (m_scanner->getCurrentToken() != Token::Identifier) + BOOST_THROW_EXCEPTION(createParserError("Expected Identifier after ','")); + } + + nodeFactory.markEndPosition(); + expectToken(Token::RBrace); + return nodeFactory.createNode<EnumDefinition>(name, members); +} + +ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration( + VarDeclParserOptions const& _options, + ASTPointer<TypeName> const& _lookAheadArrayType +) +{ + ASTNodeFactory nodeFactory = _lookAheadArrayType ? + ASTNodeFactory(*this, _lookAheadArrayType) : ASTNodeFactory(*this); + ASTPointer<TypeName> type; + if (_lookAheadArrayType) + type = _lookAheadArrayType; + else + { + type = parseTypeName(_options.allowVar); + if (type != nullptr) + nodeFactory.setEndPositionFromNode(type); + } + bool isIndexed = false; + bool isDeclaredConst = false; + Declaration::Visibility visibility(Declaration::Visibility::Default); + VariableDeclaration::Location location = VariableDeclaration::Location::Default; + ASTPointer<ASTString> identifier; + + while (true) + { + Token::Value token = m_scanner->getCurrentToken(); + if (_options.isStateVariable && Token::isVariableVisibilitySpecifier(token)) + { + if (visibility != Declaration::Visibility::Default) + BOOST_THROW_EXCEPTION(createParserError("Visibility already specified.")); + visibility = parseVisibilitySpecifier(token); + } + else + { + if (_options.allowIndexed && token == Token::Indexed) + isIndexed = true; + else if (token == Token::Const) + isDeclaredConst = true; + else if (_options.allowLocationSpecifier && Token::isLocationSpecifier(token)) + { + if (location != VariableDeclaration::Location::Default) + BOOST_THROW_EXCEPTION(createParserError("Location already specified.")); + if (!type) + BOOST_THROW_EXCEPTION(createParserError("Location specifier needs explicit type name.")); + location = ( + token == Token::Memory ? + VariableDeclaration::Location::Memory : + VariableDeclaration::Location::Storage + ); + } + else + break; + m_scanner->next(); + } + } + nodeFactory.markEndPosition(); + + if (_options.allowEmptyName && m_scanner->getCurrentToken() != Token::Identifier) + { + identifier = make_shared<ASTString>(""); + solAssert(type != nullptr, ""); + nodeFactory.setEndPositionFromNode(type); + } + else + identifier = expectIdentifierToken(); + ASTPointer<Expression> value; + if (_options.allowInitialValue) + { + if (m_scanner->getCurrentToken() == Token::Assign) + { + m_scanner->next(); + value = parseExpression(); + nodeFactory.setEndPositionFromNode(value); + } + } + return nodeFactory.createNode<VariableDeclaration>( + type, + identifier, + value, + visibility, + _options.isStateVariable, + isIndexed, + isDeclaredConst, + location + ); +} + +ASTPointer<ModifierDefinition> Parser::parseModifierDefinition() +{ + ScopeGuard resetModifierFlag([this]() { m_insideModifier = false; }); + m_insideModifier = true; + + ASTNodeFactory nodeFactory(*this); + ASTPointer<ASTString> docstring; + if (m_scanner->getCurrentCommentLiteral() != "") + docstring = make_shared<ASTString>(m_scanner->getCurrentCommentLiteral()); + + expectToken(Token::Modifier); + ASTPointer<ASTString> name(expectIdentifierToken()); + ASTPointer<ParameterList> parameters; + if (m_scanner->getCurrentToken() == Token::LParen) + { + VarDeclParserOptions options; + options.allowIndexed = true; + options.allowLocationSpecifier = true; + parameters = parseParameterList(options); + } + else + parameters = createEmptyParameterList(); + ASTPointer<Block> block = parseBlock(); + nodeFactory.setEndPositionFromNode(block); + return nodeFactory.createNode<ModifierDefinition>(name, docstring, parameters, block); +} + +ASTPointer<EventDefinition> Parser::parseEventDefinition() +{ + ASTNodeFactory nodeFactory(*this); + ASTPointer<ASTString> docstring; + if (m_scanner->getCurrentCommentLiteral() != "") + docstring = make_shared<ASTString>(m_scanner->getCurrentCommentLiteral()); + + expectToken(Token::Event); + ASTPointer<ASTString> name(expectIdentifierToken()); + ASTPointer<ParameterList> parameters; + if (m_scanner->getCurrentToken() == Token::LParen) + { + VarDeclParserOptions options; + options.allowIndexed = true; + parameters = parseParameterList(options); + } + else + parameters = createEmptyParameterList(); + bool anonymous = false; + if (m_scanner->getCurrentToken() == Token::Anonymous) + { + anonymous = true; + m_scanner->next(); + } + nodeFactory.markEndPosition(); + expectToken(Token::Semicolon); + return nodeFactory.createNode<EventDefinition>(name, docstring, parameters, anonymous); +} + +ASTPointer<ModifierInvocation> Parser::parseModifierInvocation() +{ + ASTNodeFactory nodeFactory(*this); + ASTPointer<Identifier> name(parseIdentifier()); + vector<ASTPointer<Expression>> arguments; + if (m_scanner->getCurrentToken() == Token::LParen) + { + m_scanner->next(); + arguments = parseFunctionCallListArguments(); + nodeFactory.markEndPosition(); + expectToken(Token::RParen); + } + else + nodeFactory.setEndPositionFromNode(name); + return nodeFactory.createNode<ModifierInvocation>(name, arguments); +} + +ASTPointer<Identifier> Parser::parseIdentifier() +{ + ASTNodeFactory nodeFactory(*this); + nodeFactory.markEndPosition(); + return nodeFactory.createNode<Identifier>(expectIdentifierToken()); +} + +ASTPointer<TypeName> Parser::parseTypeName(bool _allowVar) +{ + ASTNodeFactory nodeFactory(*this); + ASTPointer<TypeName> type; + Token::Value token = m_scanner->getCurrentToken(); + if (Token::isElementaryTypeName(token)) + { + type = ASTNodeFactory(*this).createNode<ElementaryTypeName>(token); + m_scanner->next(); + } + else if (token == Token::Var) + { + if (!_allowVar) + BOOST_THROW_EXCEPTION(createParserError("Expected explicit type name.")); + m_scanner->next(); + } + else if (token == Token::Mapping) + type = parseMapping(); + else if (token == Token::Identifier) + { + ASTNodeFactory nodeFactory(*this); + nodeFactory.markEndPosition(); + type = nodeFactory.createNode<UserDefinedTypeName>(expectIdentifierToken()); + } + else + BOOST_THROW_EXCEPTION(createParserError("Expected type name")); + + if (type) + // Parse "[...]" postfixes for arrays. + while (m_scanner->getCurrentToken() == Token::LBrack) + { + m_scanner->next(); + ASTPointer<Expression> length; + if (m_scanner->getCurrentToken() != Token::RBrack) + length = parseExpression(); + nodeFactory.markEndPosition(); + expectToken(Token::RBrack); + type = nodeFactory.createNode<ArrayTypeName>(type, length); + } + return type; +} + +ASTPointer<Mapping> Parser::parseMapping() +{ + ASTNodeFactory nodeFactory(*this); + expectToken(Token::Mapping); + expectToken(Token::LParen); + if (!Token::isElementaryTypeName(m_scanner->getCurrentToken())) + BOOST_THROW_EXCEPTION(createParserError("Expected elementary type name for mapping key type")); + ASTPointer<ElementaryTypeName> keyType; + keyType = ASTNodeFactory(*this).createNode<ElementaryTypeName>(m_scanner->getCurrentToken()); + m_scanner->next(); + expectToken(Token::Arrow); + bool const allowVar = false; + ASTPointer<TypeName> valueType = parseTypeName(allowVar); + nodeFactory.markEndPosition(); + expectToken(Token::RParen); + return nodeFactory.createNode<Mapping>(keyType, valueType); +} + +ASTPointer<ParameterList> Parser::parseParameterList( + VarDeclParserOptions const& _options, + bool _allowEmpty +) +{ + ASTNodeFactory nodeFactory(*this); + vector<ASTPointer<VariableDeclaration>> parameters; + VarDeclParserOptions options(_options); + options.allowEmptyName = true; + expectToken(Token::LParen); + if (!_allowEmpty || m_scanner->getCurrentToken() != Token::RParen) + { + parameters.push_back(parseVariableDeclaration(options)); + while (m_scanner->getCurrentToken() != Token::RParen) + { + expectToken(Token::Comma); + parameters.push_back(parseVariableDeclaration(options)); + } + } + nodeFactory.markEndPosition(); + m_scanner->next(); + return nodeFactory.createNode<ParameterList>(parameters); +} + +ASTPointer<Block> Parser::parseBlock() +{ + ASTNodeFactory nodeFactory(*this); + expectToken(Token::LBrace); + vector<ASTPointer<Statement>> statements; + while (m_scanner->getCurrentToken() != Token::RBrace) + statements.push_back(parseStatement()); + nodeFactory.markEndPosition(); + expectToken(Token::RBrace); + return nodeFactory.createNode<Block>(statements); +} + +ASTPointer<Statement> Parser::parseStatement() +{ + ASTPointer<Statement> statement; + switch (m_scanner->getCurrentToken()) + { + case Token::If: + return parseIfStatement(); + case Token::While: + return parseWhileStatement(); + case Token::For: + return parseForStatement(); + case Token::LBrace: + return parseBlock(); + // starting from here, all statements must be terminated by a semicolon + case Token::Continue: + statement = ASTNodeFactory(*this).createNode<Continue>(); + m_scanner->next(); + break; + case Token::Break: + statement = ASTNodeFactory(*this).createNode<Break>(); + m_scanner->next(); + break; + case Token::Return: + { + ASTNodeFactory nodeFactory(*this); + ASTPointer<Expression> expression; + if (m_scanner->next() != Token::Semicolon) + { + expression = parseExpression(); + nodeFactory.setEndPositionFromNode(expression); + } + statement = nodeFactory.createNode<Return>(expression); + break; + } + case Token::Identifier: + if (m_insideModifier && m_scanner->getCurrentLiteral() == "_") + { + statement = ASTNodeFactory(*this).createNode<PlaceholderStatement>(); + m_scanner->next(); + return statement; + } + // fall-through + default: + statement = parseSimpleStatement(); + } + expectToken(Token::Semicolon); + return statement; +} + +ASTPointer<IfStatement> Parser::parseIfStatement() +{ + ASTNodeFactory nodeFactory(*this); + expectToken(Token::If); + expectToken(Token::LParen); + ASTPointer<Expression> condition = parseExpression(); + expectToken(Token::RParen); + ASTPointer<Statement> trueBody = parseStatement(); + ASTPointer<Statement> falseBody; + if (m_scanner->getCurrentToken() == Token::Else) + { + m_scanner->next(); + falseBody = parseStatement(); + nodeFactory.setEndPositionFromNode(falseBody); + } + else + nodeFactory.setEndPositionFromNode(trueBody); + return nodeFactory.createNode<IfStatement>(condition, trueBody, falseBody); +} + +ASTPointer<WhileStatement> Parser::parseWhileStatement() +{ + ASTNodeFactory nodeFactory(*this); + expectToken(Token::While); + expectToken(Token::LParen); + ASTPointer<Expression> condition = parseExpression(); + expectToken(Token::RParen); + ASTPointer<Statement> body = parseStatement(); + nodeFactory.setEndPositionFromNode(body); + return nodeFactory.createNode<WhileStatement>(condition, body); +} + +ASTPointer<ForStatement> Parser::parseForStatement() +{ + ASTNodeFactory nodeFactory(*this); + ASTPointer<Statement> initExpression; + ASTPointer<Expression> conditionExpression; + ASTPointer<ExpressionStatement> loopExpression; + expectToken(Token::For); + expectToken(Token::LParen); + + // LTODO: Maybe here have some predicate like peekExpression() instead of checking for semicolon and RParen? + if (m_scanner->getCurrentToken() != Token::Semicolon) + initExpression = parseSimpleStatement(); + expectToken(Token::Semicolon); + + if (m_scanner->getCurrentToken() != Token::Semicolon) + conditionExpression = parseExpression(); + expectToken(Token::Semicolon); + + if (m_scanner->getCurrentToken() != Token::RParen) + loopExpression = parseExpressionStatement(); + expectToken(Token::RParen); + + ASTPointer<Statement> body = parseStatement(); + nodeFactory.setEndPositionFromNode(body); + return nodeFactory.createNode<ForStatement>(initExpression, + conditionExpression, + loopExpression, + body); +} + +ASTPointer<Statement> Parser::parseSimpleStatement() +{ + // These two cases are very hard to distinguish: + // x[7 * 20 + 3] a; - x[7 * 20 + 3] = 9; + // In the first case, x is a type name, in the second it is the name of a variable. + switch (peekStatementType()) + { + case LookAheadInfo::VariableDeclarationStatement: + return parseVariableDeclarationStatement(); + case LookAheadInfo::ExpressionStatement: + return parseExpressionStatement(); + default: + break; + } + + // At this point, we have '(Identifier|ElementaryTypeName) "["'. + // We parse '(Identifier|ElementaryTypeName) ( "[" Expression "]" )+' and then decide whether to hand this over + // to ExpressionStatement or create a VariableDeclarationStatement out of it. + ASTPointer<PrimaryExpression> primary; + if (m_scanner->getCurrentToken() == Token::Identifier) + primary = parseIdentifier(); + else + { + primary = ASTNodeFactory(*this).createNode<ElementaryTypeNameExpression>(m_scanner->getCurrentToken()); + m_scanner->next(); + } + vector<pair<ASTPointer<Expression>, SourceLocation>> indices; + solAssert(m_scanner->getCurrentToken() == Token::LBrack, ""); + SourceLocation indexLocation = primary->getLocation(); + do + { + expectToken(Token::LBrack); + ASTPointer<Expression> index; + if (m_scanner->getCurrentToken() != Token::RBrack) + index = parseExpression(); + indexLocation.end = getEndPosition(); + indices.push_back(make_pair(index, indexLocation)); + expectToken(Token::RBrack); + } + while (m_scanner->getCurrentToken() == Token::LBrack); + + if (m_scanner->getCurrentToken() == Token::Identifier || Token::isLocationSpecifier(m_scanner->getCurrentToken())) + return parseVariableDeclarationStatement(typeNameIndexAccessStructure(primary, indices)); + else + return parseExpressionStatement(expressionFromIndexAccessStructure(primary, indices)); +} + +ASTPointer<VariableDeclarationStatement> Parser::parseVariableDeclarationStatement( + ASTPointer<TypeName> const& _lookAheadArrayType) +{ + VarDeclParserOptions options; + options.allowVar = true; + options.allowInitialValue = true; + options.allowLocationSpecifier = true; + ASTPointer<VariableDeclaration> variable = parseVariableDeclaration(options, _lookAheadArrayType); + ASTNodeFactory nodeFactory(*this, variable); + return nodeFactory.createNode<VariableDeclarationStatement>(variable); +} + +ASTPointer<ExpressionStatement> Parser::parseExpressionStatement( + ASTPointer<Expression> const& _lookAheadIndexAccessStructure) +{ + ASTPointer<Expression> expression = parseExpression(_lookAheadIndexAccessStructure); + return ASTNodeFactory(*this, expression).createNode<ExpressionStatement>(expression); +} + +ASTPointer<Expression> Parser::parseExpression( + ASTPointer<Expression> const& _lookAheadIndexAccessStructure) +{ + ASTPointer<Expression> expression = parseBinaryExpression(4, _lookAheadIndexAccessStructure); + if (!Token::isAssignmentOp(m_scanner->getCurrentToken())) + return expression; + Token::Value assignmentOperator = expectAssignmentOperator(); + ASTPointer<Expression> rightHandSide = parseExpression(); + ASTNodeFactory nodeFactory(*this, expression); + nodeFactory.setEndPositionFromNode(rightHandSide); + return nodeFactory.createNode<Assignment>(expression, assignmentOperator, rightHandSide); +} + +ASTPointer<Expression> Parser::parseBinaryExpression(int _minPrecedence, + ASTPointer<Expression> const& _lookAheadIndexAccessStructure) +{ + ASTPointer<Expression> expression = parseUnaryExpression(_lookAheadIndexAccessStructure); + ASTNodeFactory nodeFactory(*this, expression); + int precedence = Token::precedence(m_scanner->getCurrentToken()); + for (; precedence >= _minPrecedence; --precedence) + while (Token::precedence(m_scanner->getCurrentToken()) == precedence) + { + Token::Value op = m_scanner->getCurrentToken(); + m_scanner->next(); + ASTPointer<Expression> right = parseBinaryExpression(precedence + 1); + nodeFactory.setEndPositionFromNode(right); + expression = nodeFactory.createNode<BinaryOperation>(expression, op, right); + } + return expression; +} + +ASTPointer<Expression> Parser::parseUnaryExpression( + ASTPointer<Expression> const& _lookAheadIndexAccessStructure) +{ + ASTNodeFactory nodeFactory = _lookAheadIndexAccessStructure ? + ASTNodeFactory(*this, _lookAheadIndexAccessStructure) : ASTNodeFactory(*this); + Token::Value token = m_scanner->getCurrentToken(); + if (!_lookAheadIndexAccessStructure && (Token::isUnaryOp(token) || Token::isCountOp(token))) + { + // prefix expression + m_scanner->next(); + ASTPointer<Expression> subExpression = parseUnaryExpression(); + nodeFactory.setEndPositionFromNode(subExpression); + return nodeFactory.createNode<UnaryOperation>(token, subExpression, true); + } + else + { + // potential postfix expression + ASTPointer<Expression> subExpression = parseLeftHandSideExpression(_lookAheadIndexAccessStructure); + token = m_scanner->getCurrentToken(); + if (!Token::isCountOp(token)) + return subExpression; + nodeFactory.markEndPosition(); + m_scanner->next(); + return nodeFactory.createNode<UnaryOperation>(token, subExpression, false); + } +} + +ASTPointer<Expression> Parser::parseLeftHandSideExpression( + ASTPointer<Expression> const& _lookAheadIndexAccessStructure) +{ + ASTNodeFactory nodeFactory = _lookAheadIndexAccessStructure ? + ASTNodeFactory(*this, _lookAheadIndexAccessStructure) : ASTNodeFactory(*this); + + ASTPointer<Expression> expression; + if (_lookAheadIndexAccessStructure) + expression = _lookAheadIndexAccessStructure; + else if (m_scanner->getCurrentToken() == Token::New) + { + expectToken(Token::New); + ASTPointer<Identifier> contractName(parseIdentifier()); + nodeFactory.setEndPositionFromNode(contractName); + expression = nodeFactory.createNode<NewExpression>(contractName); + } + else + expression = parsePrimaryExpression(); + + while (true) + { + switch (m_scanner->getCurrentToken()) + { + case Token::LBrack: + { + m_scanner->next(); + ASTPointer<Expression> index; + if (m_scanner->getCurrentToken() != Token::RBrack) + index = parseExpression(); + nodeFactory.markEndPosition(); + expectToken(Token::RBrack); + expression = nodeFactory.createNode<IndexAccess>(expression, index); + } + break; + case Token::Period: + { + m_scanner->next(); + nodeFactory.markEndPosition(); + expression = nodeFactory.createNode<MemberAccess>(expression, expectIdentifierToken()); + } + break; + case Token::LParen: + { + m_scanner->next(); + vector<ASTPointer<Expression>> arguments; + vector<ASTPointer<ASTString>> names; + std::tie(arguments, names) = parseFunctionCallArguments(); + nodeFactory.markEndPosition(); + expectToken(Token::RParen); + expression = nodeFactory.createNode<FunctionCall>(expression, arguments, names); + } + break; + default: + return expression; + } + } +} + +ASTPointer<Expression> Parser::parsePrimaryExpression() +{ + ASTNodeFactory nodeFactory(*this); + Token::Value token = m_scanner->getCurrentToken(); + ASTPointer<Expression> expression; + switch (token) + { + case Token::TrueLiteral: + case Token::FalseLiteral: + expression = nodeFactory.createNode<Literal>(token, getLiteralAndAdvance()); + break; + case Token::Number: + if (Token::isEtherSubdenomination(m_scanner->peekNextToken())) + { + ASTPointer<ASTString> literal = getLiteralAndAdvance(); + nodeFactory.markEndPosition(); + Literal::SubDenomination subdenomination = static_cast<Literal::SubDenomination>(m_scanner->getCurrentToken()); + m_scanner->next(); + expression = nodeFactory.createNode<Literal>(token, literal, subdenomination); + break; + } + if (Token::isTimeSubdenomination(m_scanner->peekNextToken())) + { + ASTPointer<ASTString> literal = getLiteralAndAdvance(); + nodeFactory.markEndPosition(); + Literal::SubDenomination subdenomination = static_cast<Literal::SubDenomination>(m_scanner->getCurrentToken()); + m_scanner->next(); + expression = nodeFactory.createNode<Literal>(token, literal, subdenomination); + break; + } + // fall-through + case Token::StringLiteral: + nodeFactory.markEndPosition(); + expression = nodeFactory.createNode<Literal>(token, getLiteralAndAdvance()); + break; + case Token::Identifier: + nodeFactory.markEndPosition(); + expression = nodeFactory.createNode<Identifier>(getLiteralAndAdvance()); + break; + case Token::LParen: + { + m_scanner->next(); + ASTPointer<Expression> expression = parseExpression(); + expectToken(Token::RParen); + return expression; + } + default: + if (Token::isElementaryTypeName(token)) + { + // used for casts + expression = nodeFactory.createNode<ElementaryTypeNameExpression>(token); + m_scanner->next(); + } + else + BOOST_THROW_EXCEPTION(createParserError("Expected primary expression.")); + break; + } + return expression; +} + +vector<ASTPointer<Expression>> Parser::parseFunctionCallListArguments() +{ + vector<ASTPointer<Expression>> arguments; + if (m_scanner->getCurrentToken() != Token::RParen) + { + arguments.push_back(parseExpression()); + while (m_scanner->getCurrentToken() != Token::RParen) + { + expectToken(Token::Comma); + arguments.push_back(parseExpression()); + } + } + return arguments; +} + +pair<vector<ASTPointer<Expression>>, vector<ASTPointer<ASTString>>> Parser::parseFunctionCallArguments() +{ + pair<vector<ASTPointer<Expression>>, vector<ASTPointer<ASTString>>> ret; + Token::Value token = m_scanner->getCurrentToken(); + if (token == Token::LBrace) + { + // call({arg1 : 1, arg2 : 2 }) + expectToken(Token::LBrace); + while (m_scanner->getCurrentToken() != Token::RBrace) + { + ret.second.push_back(expectIdentifierToken()); + expectToken(Token::Colon); + ret.first.push_back(parseExpression()); + + if (m_scanner->getCurrentToken() == Token::Comma) + expectToken(Token::Comma); + else + break; + } + expectToken(Token::RBrace); + } + else + ret.first = parseFunctionCallListArguments(); + return ret; +} + +Parser::LookAheadInfo Parser::peekStatementType() const +{ + // Distinguish between variable declaration (and potentially assignment) and expression statement + // (which include assignments to other expressions and pre-declared variables). + // We have a variable declaration if we get a keyword that specifies a type name. + // If it is an identifier or an elementary type name followed by an identifier, we also have + // a variable declaration. + // If we get an identifier followed by a "[", it can be both ("type[9] a;" or "arr[9] = 7;"). + // In all other cases, we have an expression statement. + Token::Value token(m_scanner->getCurrentToken()); + bool mightBeTypeName = (Token::isElementaryTypeName(token) || token == Token::Identifier); + + if (token == Token::Mapping || token == Token::Var) + return LookAheadInfo::VariableDeclarationStatement; + if (mightBeTypeName) + { + Token::Value next = m_scanner->peekNextToken(); + if (next == Token::Identifier || Token::isLocationSpecifier(next)) + return LookAheadInfo::VariableDeclarationStatement; + if (m_scanner->peekNextToken() == Token::LBrack) + return LookAheadInfo::IndexAccessStructure; + } + return LookAheadInfo::ExpressionStatement; +} + +ASTPointer<TypeName> Parser::typeNameIndexAccessStructure( + ASTPointer<PrimaryExpression> const& _primary, vector<pair<ASTPointer<Expression>, SourceLocation>> const& _indices) +{ + ASTNodeFactory nodeFactory(*this, _primary); + ASTPointer<TypeName> type; + if (auto identifier = dynamic_cast<Identifier const*>(_primary.get())) + type = nodeFactory.createNode<UserDefinedTypeName>(make_shared<ASTString>(identifier->getName())); + else if (auto typeName = dynamic_cast<ElementaryTypeNameExpression const*>(_primary.get())) + type = nodeFactory.createNode<ElementaryTypeName>(typeName->getTypeToken()); + else + solAssert(false, "Invalid type name for array look-ahead."); + for (auto const& lengthExpression: _indices) + { + nodeFactory.setLocation(lengthExpression.second); + type = nodeFactory.createNode<ArrayTypeName>(type, lengthExpression.first); + } + return type; +} + +ASTPointer<Expression> Parser::expressionFromIndexAccessStructure( + ASTPointer<PrimaryExpression> const& _primary, vector<pair<ASTPointer<Expression>, SourceLocation>> const& _indices) +{ + ASTNodeFactory nodeFactory(*this, _primary); + ASTPointer<Expression> expression(_primary); + for (auto const& index: _indices) + { + nodeFactory.setLocation(index.second); + expression = nodeFactory.createNode<IndexAccess>(expression, index.first); + } + return expression; +} + +void Parser::expectToken(Token::Value _value) +{ + if (m_scanner->getCurrentToken() != _value) + BOOST_THROW_EXCEPTION(createParserError(string("Expected token ") + string(Token::getName(_value)))); + m_scanner->next(); +} + +Token::Value Parser::expectAssignmentOperator() +{ + Token::Value op = m_scanner->getCurrentToken(); + if (!Token::isAssignmentOp(op)) + BOOST_THROW_EXCEPTION(createParserError("Expected assignment operator")); + m_scanner->next(); + return op; +} + +ASTPointer<ASTString> Parser::expectIdentifierToken() +{ + if (m_scanner->getCurrentToken() != Token::Identifier) + BOOST_THROW_EXCEPTION(createParserError("Expected identifier")); + return getLiteralAndAdvance(); +} + +ASTPointer<ASTString> Parser::getLiteralAndAdvance() +{ + ASTPointer<ASTString> identifier = make_shared<ASTString>(m_scanner->getCurrentLiteral()); + m_scanner->next(); + return identifier; +} + +ASTPointer<ParameterList> Parser::createEmptyParameterList() +{ + ASTNodeFactory nodeFactory(*this); + nodeFactory.setLocationEmpty(); + return nodeFactory.createNode<ParameterList>(vector<ASTPointer<VariableDeclaration>>()); +} + +ParserError Parser::createParserError(string const& _description) const +{ + return ParserError() << errinfo_sourceLocation(SourceLocation(getPosition(), getPosition(), getSourceName())) + << errinfo_comment(_description); +} + + +} +} |